The present invention relates to an apparatus for molding and solidifying molten soap into a prescribed shape to produce soap cakes and a mold to be used in the apparatus. It also relates to a method of producing soap cakes by molding and solidifying molten soap into a prescribed shape.
U.S. Pat. No. 2,987,484 discloses a process of making soap bars comprising injecting molten soap circulating in a circulating duct into the cavity of a mold and solidifying the molten soap in the cavity. The mold has an injection valve in the gate. With the injection valve in the backward position, molten soap is injected into the cavity through the gate. Because the injection valve is smaller in size than the gate, after the injection valve advances to shut the injection port of the cavity, molten soap remains in the gap formed between the injection valve and the gate. The remaining molten soap does not return to the circulating duct and gradually cools and solidifies there. Therefore, the remaining soap should be removed before the next shot, which results in poor productivity. If the soap is not removed, it can cause faults in the subsequent molding cycle and impede obtaining homogeneous products.
WO98/53039 discloses a method of producing soap, in which when molten soap is injected through a nozzle into a mold from the top of the mold, the mold is vertically moved down in accordance with the liquid level of molten soap injected so that the tip of the nozzle may always be positioned immediately above the liquid level. In this method, too, molten soap remains in the nozzle after mold filling, giving rise to necessity to remove solidified soap before the next shot.